Wagner power painters...?

I used to paint apartment interiors regularly, and the consumer power painter was a really good investment for me.
I was able to control the spreay well enouth that I didn't need to mask the baseboard (but i did mask windows).
IMO, there is a design flaw, that could be easily corrected- the shape of the hopper is larger at the bottom, causing the pickup tube to suck air when the hopper becomes about half full (by fluid height and about 2/3 full by volume) and slightly tilted. This will cause a splatter.
This also causes the need to refill the hopper much more frequently.
If the hopper design were inverted, it would be MUCH more efficient.
You could go longer between filling and it would not cause 2/3 of the contents of the hoper to be useless.

I also painted the exterior of my mom's house with that same power painter in 1993- with a single coat (in about 45 minutes)...and it is just now starting to show thin in spots!! (that's almost 20 YEARS)

...and unfortunately the cleanup sucks.

I now have a more commercial brand (whatever Lowes sells), and as nice as it is, with a cylindrical hopper, it is much more difficult to control the thickness of the paint and the fan of the spray.